MKSAP Quiz: Abrupt-onset abdominal cramping
An 80-year-old woman is hospitalized for a 1-day history of abrupt-onset, mild, diffuse lower abdominal cramping and discomfort, followed several hours later by initially loose, nonbloody stools that evolved into hematochezia. What is the most likely diagnosis?
An 80-year-old woman is hospitalized for a 1-day history of abrupt-onset, mild, diffuse lower abdominal cramping and discomfort, followed several hours later by initially loose, nonbloody stools that evolved into hematochezia. She has subsequently passed six bloody stools. She has no fever, chills, nausea, or melenic stool. She reports no recent exposure to sick persons, antibiotic use, travel, or NSAID use. She has hypertension, osteoarthritis, and hypothyroidism. Medications are hydrochlorothiazide, acetaminophen, and levothyroxine.
On physical examination, blood pressure is 150/85 mm Hg. Other vital signs are normal. Abdominal examination shows mild mid-abdominal tenderness to deep palpation, no distention, and no rebound or guarding. Rectal examination reveals a small amount of bright red blood on the examining finger.
Laboratory studies:
| Leukocyte count | 14,000/μL (14 × 109/L) (85% neutrophils) (High) |
| Hemoglobin | 12.5 g/dL (125 g/L) |
| Platelet count | 205,000/μL (205 × 109/L) |
| Blood urea nitrogen | 16 mg/dL (5.7 mmol/L) |
| Creatinine | 0.7 mg/dL (61.9 μmol/L) |
CT scan of the abdomen and pelvis with intravenous contrast shows marked wall thickening of the transverse and descending colon with patent arterial and venous vessels. There are no mass lesions or diverticula.
Which of the following is the most likely diagnosis?
A. Colonic ischemia
B. Crohn disease
C. Infectious colitis
D. Ulcerative colitis
MKSAP Answer and Critique
The correct answer is A. Colonic ischemia. This content is available to ACP MKSAP subscribers in the Gastroenterology and Hepatology section. More information about ACP MKSAP is available online.
The most likely diagnosis is colonic ischemia (Option A). Colonic ischemia characteristically presents with abrupt onset of lower abdominal discomfort that is mild to moderate and cramping in nature, followed within 24 hours by diarrhea and hematochezia. Colonic ischemia most commonly results from a nonocclusive low-flow state in microvessels that occurs with hypovolemia or hypotension. Risk factors include age older than 60 years, female sex, and use of antihypertensive medications. Physical examination most commonly reveals mild lower abdominal tenderness over the involved bowel segment without peritoneal signs. Laboratory studies may show mildly elevated leukocyte count. CT findings in colonic ischemia are nonspecific and include bowel-wall thickening, often in a segmental distribution corresponding to the “watershed” areas of the colon (e.g., splenic flexure). This patient's presentation with sudden onset of mild lower abdominal discomfort, followed within 24 hours by diarrhea and hematochezia, is a classic presentation of colonic ischemia, which is the most common form of ischemic bowel disease.
Crohn disease (Option B) can cause abdominal discomfort and hematochezia, and CT scan may show features of segmental colonic thickening; however, the abrupt onset of symptoms in this patient and her older age make Crohn disease unlikely.
Infectious colitis (Option C) due to cytomegalovirus, Clostridioides difficile, or Shiga toxin–producing Escherichia coli can mimic colonic ischemia in symptom presentation and on CT scans, so it must be excluded by stool testing before a diagnosis of colonic ischemia is secure. However, infectious colitis is less likely than colonic ischemia in this patient because she lacks infectious risk factors, such as sick contacts, recent travel, or recent use of antibiotics.
Ulcerative colitis (Option D) often presents with the insidious onset of abdominal discomfort and hematochezia. The inflammatory mucosal changes of ulcerative colitis involve the colon in a diffuse and symmetric fashion beginning in the rectum and extending more proximally. This patient had an abrupt onset of symptoms, and the CT scan shows segmental colonic thickening involving only the transverse and descending colon; these would be unusual findings in ulcerative colitis.
Key Point
- Colonic ischemia presents with the abrupt onset of cramping and mild to moderate lower abdominal discomfort, followed within 24 hours by diarrhea and hematochezia.